Applied patch series for LD plugin interface (six parts).

[PATCH] Add infrastructure for plugin API; functionality to follow.

    include/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 1/6).
	* plugin-api.h (LDPT_GNU_LD_VERSION): New ld_plugin_tag enum member.

    ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 1/6).
	* configure.in: Add AC_CHECKs for file io and dlfcn headers and
	functions and AC_SEARCH for -ldl.
	(enable_plugins): New shell variable set if above tests find dlopen
	functionality.
	(ENABLE_PLUGINS): Add related automake conditional.
	* configure: Regenerate.
	* config.in: Likewise.
	* Makefile.am (PLUGIN_C): Declare plugin C source file, conditional
	on ENABLE_PLUGINS being defined.
	(PLUGIN_H): Likewise for header file.
	(PLUGIN_OBJECT): Likewise for object file.
	(PLUGIN_CFLAGS): Likewise -D flag required to compile plugin support.
	(AM_CPPFLAGS): Use PLUGIN_CFLAGS.
	(CFILES): Use PLUGIN_C.
	(HFILES): Use PLUGIN_H.
	(OFILES): Use PLUGIN_OBJECT.
	(ld_new_SOURCES): Use PLUGIN_C.
	(noinst_LTLIBRARIES)[ENABLE_PLUGINS]: Declare test plugin.
	(libldtestplug_la_SOURCES)[ENABLE_PLUGINS]: Add automake definition
	for test plugin.
	(libldtestplug_la_CFLAGS)[ENABLE_PLUGINS]: Likewise.
	(libldtestplug_la_LDFLAGS)[ENABLE_PLUGINS]: Likewise.
	* Makefile.in: Regenerate.
	* sysdep.h: Include stdarg.h, unistd.h and one of fcntl.h or
	sys/file.h where available.  Include dlfcn.h when ENABLE_PLUGINS.
	(O_RDONLY): Supply default definition likewise to bfd's sysdep.h
	(O_WRONLY): Likewise.
	(O_RDWR): Likewise.
	(O_ACCMODE): Likewise.
	(O_BINARY): Likewise.
	(SEEK_SET): Likewise.
	(SEEK_CUR): Likewise.
	(SEEK_END): Likewise.
	* ldmisc.c (vfinfo): Make non-static.  Add %p format char.
	* ldmisc.h (vfinfo): Declare extern prototype.
	* lexsup.c (enum option_values)[ENABLE_PLUGINS]: Add new entries for
	OPTION_PLUGIN and OPTION_PLUGIN_OPT.
	(ld_options[])[ENABLE_PLUGINS]: Add option data for the above two.
	(parse_args)[ENABLE_PLUGINS]: Handle them, and load all plugins once
	option parsing is complete.
	* ldmain.c (main)[ENABLE_PLUGINS]: Call plugin cleanup hooks just
	after lang_finish.
	* plugin.c: New source file.
	* plugin.h: Likewise new header.
	* testplug.c: New source file.

    ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 1/6).
	* ld-bootstrap/bootstrap.exp: Skip static tests also if LD plugins
	are enabled.
	* lib/ld-lib.exp (proc regexp_diff): Extend verbose debug output.
	(proc set_file_contents): Write a file with the supplied content.
	(run_ld_link_tests): Add new 'ld' action to test linker output.
	(proc check_plugin_api_available): Return true if linker under test
	supports the plugin API.
	* ld-plugin/func.c: New test source file.
	* ld-plugin/main.c: Likewise.
	* ld-plugin/text.c: Likewise.
	* ld-plugin/plugin-1.d: New dump test output pattern script.
	* ld-plugin/plugin-2.d: Likewise.
	* ld-plugin/plugin-3.d: Likewise.
	* ld-plugin/plugin-4.d: Likewise.
	* ld-plugin/plugin-5.d: Likewise.
	* ld-plugin/plugin.exp: New test control script.
---
[PATCH] Implement claim file and all symbols read hooks and add symbols callback.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 2/6).
	* ldfile.c (ldfile_try_open_bfd)[ENABLE_PLUGINS]: Don't return early
	during compat checks if they pass, instead offer any successfully
	opened and accepted file to the plugin claim file hooks chain.  Create
	a dummy bfd to accept symbols added by the plugin, if the plugin
	claims the file.
	* ldlang.c (lang_process)[ENABLE_PLUGINS]: Call plugin all symbols
	read hook chain before ldemul_after_open.
	* ldlang.h (struct lang_input_statement_struct): Add new single-bit
	'claimed' flag.
	* plugin.c (IRONLY_SUFFIX): New macro for dummy bfd file suffix.
	(IRONLY_SUFFIX_LEN): Length of the above string.
	(plugin_get_ir_dummy_bfd): New function to create the dummy bfd used
	to store symbols for ir-only files.
	(is_ir_dummy_bfd): New function to check if a bfd is ir-only.
	(asymbol_from_plugin_symbol): New function converts symbol formats.
	(add_symbols): Call it to convert plugin syms to bfd syms and add
	them to the dummy bfd.
	* plugin.h: Add missing include guards.
	(plugin_get_ir_dummy_bfd): Add prototype.
	(is_ir_dummy_bfd): Likewise.
	* testplug.c (TV_MESSAGE): New helper macro.
	(struct claim_file): New struct.
	(claim_file_t): New typedef.
	(tag_names[]): Make static and const.
	(claimfiles_list): New variable.
	(claimfiles_tail_chain_ptr): Likewise.
	(last_claimfile): Likewise.
	(record_claim_file): Record a file to claim on a singly-linked list.
	(parse_symdefstr): Parse an ASCII representation of a symbol from a
	plugin option into the fields of a struct ld_plugin_symbol.
	(record_claimed_file_symbol):  Use it to parse plugin option for
	adding a symbol.
	(parse_option): Parse claim file and add symbol options.
	(dump_tv_tag): Use TV_MESSAGE.
	(onload): Likewise.
	(onclaim_file): Make static.  Use TV_MESSAGE.  Scan list of files to
	claim and claim this file if required, adding any symbols specified.
	(onall_symbols_read): Make static and use TV_MESSAGE.
	(oncleanup): Likewise.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 2/6).
	* ld-plugin/plugin-3.d: Enable regexes for new functionality.
	* ld-plugin/plugin-5.d: Likewise.
	* ld-plugin/plugin-6.d: New testcase.
	* ld-plugin/plugin-7.d: Likewise.
	* ld-plugin/plugin.exp: Use 'nm' on compiled test objects to determine
	whether symbols in plugin arguments need an underscore prefix.  Add
	new plugin-6.d and plugin-7.d testcases.
---
[PATCH] Implement get symbols callback.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 3/6).
	* ldmain.c (notice)[ENABLE_PLUGINS]: Call plugin_notice.
	* plugin.c (non_ironly_hash): Add new bfd hash table.
	(plugin_load_plugins): Exit early if no plugins to load.  If plugins
	do load successfully, set notice_all flag in link info.
	(get_symbols): Implement.
	(plugin_load_plugins): Exit early if no plugins to load, else after
	loading plugins successfully enable notice_all mode.
	(init_non_ironly_hash): Lazily init non_ironly_hash table.
	(plugin_notice): Record symbols referenced from non-IR files in the
	non_ironly_hash.  Suppress tracing, cref generation and nocrossrefs
	tracking for symbols from dummy IR bfds.
	* plugin.h: Fix formatting.
	(plugin_notice): Add prototype.
	* testplug.c (dumpresolutions): New global var.
	(parse_options): Accept "dumpresolutions".
	(onall_symbols_read): Get syms and dump resolutions if it was given.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 3/6).
	* ld-plugin/plugin-8.d: New testcase.
	* ld-plugin/plugin.exp: Invoke it.
---
[PATCH] Implement add input file, add input lib and set extra lib path callbacks.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 4/6).
	* ldlang.c (lang_process)[ENABLE_PLUGINS]: Move invocation of
	plugin_call_all_symbols_read to before setting of gc_sym_list, and
	open any new input files that may have been added during it.
	* ldmain.c (multiple_definition)[ENABLE_PLUGINS]: Call out to
	plugin_multiple_definition and let it have first say over what to do
	with the clashing definitions.
	* plugin.c (no_more_claiming): New boolean variable.
	(plugin_cached_allow_multiple_defs): Likewise.
	(add_input_file): Implement.
	(add_input_library): Likewise.
	(set_extra_library_path): Likewise.
	(plugin_call_claim_file): Don't do anything when no_more_claiming set.
	(plugin_call_all_symbols_read): Set it.  Disable link info
	"allow_multiple_definition" flag, but cache its value.
	(plugin_multiple_definition): New function.
	* plugin.h (plugin_multiple_definition): Add prototype.
	* testplug.c (addfile_enum_t): New enumerated typedef.
	(add_file_t): New struct typedef.
	(addfiles_list): New variable.
	(addfiles_tail_chain_ptr): Likewise.
	(record_add_file): New function.
	(parse_option): Parse "add:", "lib:" and "dir:" options and call it.
	(onall_symbols_read): Iterate the list of new files, libs and dirs,
	adding them.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 4/6).
	* ld-plugin/plugin-9.d: New testcase.
	* ld-plugin/plugin.exp: Invoke it.
---
[PATCH] Add ELF symbol visibility support to plugin interface.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 5/6).
	* plugin.c (asymbol_from_plugin_symbol): If the bfd is an ELF bfd,
	find the elf symbol data and set the visibility in the st_other field.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 5/6).
	* ld-plugin/plugin-ignore.d: New dump test control script.
	* ld-plugin/plugin-vis-1.d: Likewise.
	* ld-plugin/plugin.exp: Add list of ELF-only tests and run them if
	testing on an ELF target.
---
[PATCH] Add archive support to plugin interface.

  bfd/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* aoutx.h (aout_link_check_ar_symbols): Take new "subsbfd" reference
	parameter and pass it when invoking add_archive_element callback.
	(aout_link_check_archive_element): Handle substitute bfd if it
	was set during add_archive_element callback in the above.
	* cofflink.c (coff_link_check_ar_symbols): Take new "subsbfd" reference
	parameter and pass it when invoking add_archive_element callback.
	(coff_link_check_archive_element): Handle substitute bfd if it
	was set during add_archive_element callback in the above.
	* ecoff.c (read_ext_syms_and_strs): New function holds symbol-reading
	code factored-out from ecoff_link_check_archive_element.
	(reread_ext_syms_and_strs): Clear old symbols and call it.
	(ecoff_link_check_archive_element):  Use the above.  Handle substitute
	BFD if one is set by add_archive_element callback.
	(ecoff_link_add_archive_symbols): Likewise allow bfd substitution.
	* elflink.c (elf_link_add_archive_symbols): Likewise.
	* linker.c (generic_link_check_archive_element): Likewise.
	* pdp11.c (aout_link_check_ar_symbols): Take new "subsbfd" reference
	parameter and pass it when invoking add_archive_element callback.
	(aout_link_check_archive_element): Handle substitute bfd if it was
	set during add_archive_element callback in the above.
	* vms-alpha.c (alpha_vms_link_add_archive_symbols): Handle substitute
	BFD if one is set by add_archive_element callback.
	* xcofflink.c (xcoff_link_check_dynamic_ar_symbols): Take new "subsbfd"
	reference parameter and pass it when invoking add_archive_element
	callback.
	(xcoff_link_check_ar_symbols): Likewise.
	(xcoff_link_check_archive_element): Handle bfd substitution if it was
	set by callback in the above.

  include/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* bfdlink.h (struct_bfd_link_callbacks): Document new argument
	to add_archive_element callback used to return a replacement bfd which
	is to be added to the hash table in place of the original element.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* ldlang.c (load_symbols): Handle bfd subsitution when calling the
	add_archive_element callback.
	* ldmain.c (add_archive_element)[ENABLE_PLUGINS]: Offer the archive
	member to the plugins and if claimed set "subsbfd" output parameter to
	point to the dummy IR-only BFD.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* ld-plugin/plugin-10.d: New dump test control script.
	* ld-plugin/plugin-11.d: Likewise.
	* ld-plugin/plugin.exp: Run them.
---

1 files changed, 88 insertions, 8 deletions

diff --git a/ld/ldmain.c b/ld/ldmain.c
index 08679ec..04b5633 100644
--- a/ld/ldmain.c
+++ b/ld/ldmain.c
@@ -40,6 +40,11 @@
 #include "ldfile.h"
 #include "ldemul.h"
 #include "ldctor.h"
+#ifdef ENABLE_PLUGINS
+#include "plugin.h"
+#include "plugin-api.h"
+#include "libbfd.h"
+#endif /* ENABLE_PLUGINS */
 
 /* Somewhere above, sys/stat.h got included.  */
 #if !defined(S_ISDIR) && defined(S_IFDIR)
@@ -116,7 +121,7 @@ static const char *get_sysroot
 static char *get_emulation
   (int, char **);
 static bfd_boolean add_archive_element
-  (struct bfd_link_info *, bfd *, const char *);
+  (struct bfd_link_info *, bfd *, const char *, bfd **);
 static bfd_boolean multiple_definition
   (struct bfd_link_info *, const char *, bfd *, asection *, bfd_vma,
    bfd *, asection *, bfd_vma);
@@ -474,6 +479,12 @@ main (int argc, char **argv)
 
   lang_finish ();
 
+#ifdef ENABLE_PLUGINS
+  /* Now everything is finished, we can tell the plugins to clean up.  */
+  if (plugin_call_cleanup ())
+    info_msg (_("%P: %s: error in plugin cleanup (ignored)\n"), plugin_error_plugin ());
+#endif /* ENABLE_PLUGINS */
+
   /* Even if we're producing relocatable output, some non-fatal errors should
      be reported in the exit status.  (What non-fatal errors, if any, do we
      want to ignore for relocatable output?)  */
@@ -781,9 +792,11 @@ add_keepsyms_file (const char *filename)
 static bfd_boolean
 add_archive_element (struct bfd_link_info *info,
 		     bfd *abfd,
-		     const char *name)
+		     const char *name,
+		     bfd **subsbfd ATTRIBUTE_UNUSED)
 {
   lang_input_statement_type *input;
+  lang_input_statement_type orig_input;
 
   input = (lang_input_statement_type *)
       xcalloc (1, sizeof (lang_input_statement_type));
@@ -791,6 +804,52 @@ add_archive_element (struct bfd_link_info *info,
   input->local_sym_name = abfd->filename;
   input->the_bfd = abfd;
 
+  /* Save the original data for trace files/tries below, as plugins
+     (if enabled) may possibly alter it to point to a replacement
+     BFD, but we still want to output the original BFD filename.  */
+  orig_input = *input;
+#ifdef ENABLE_PLUGINS
+  if (bfd_my_archive (abfd) != NULL)
+    {
+      /* We must offer this archive member to the plugins to claim.  */
+      int fd = open (bfd_my_archive (abfd)->filename, O_RDONLY | O_BINARY);
+      if (fd >= 0)
+	{
+	  struct ld_plugin_input_file file;
+	  int claimed = 0;
+	  /* Offset and filesize must refer to the individual archive
+	     member, not the whole file, and must exclude the header.
+	     Fortunately for us, that is how the data is stored in the
+	     origin field of the bfd and in the arelt_data.  */
+	  file.name = bfd_my_archive (abfd)->filename;
+	  file.offset = abfd->origin;
+	  file.filesize = arelt_size (abfd);
+	  file.fd = fd;
+	  /* We create a dummy BFD, initially empty, to house
+	     whatever symbols the plugin may want to add.  */
+	  file.handle = plugin_get_ir_dummy_bfd (abfd->filename, abfd);
+	  if (plugin_call_claim_file (&file, &claimed))
+	    einfo (_("%P%F: %s: plugin reported error claiming file\n"),
+	      plugin_error_plugin ());
+	  if (claimed)
+	    {
+	      /* Substitute the dummy BFD.  */
+	      input->the_bfd = file.handle;
+	      input->claimed = TRUE;
+	      bfd_make_readable (input->the_bfd);
+	      *subsbfd = input->the_bfd;
+	    }
+	  else
+	    {
+	      /* Abandon the dummy BFD.  */
+	      bfd_close_all_done (file.handle);
+	      close (fd);
+	      input->claimed = FALSE;
+	    }
+	}
+    }
+#endif /* ENABLE_PLUGINS */
+
   ldlang_add_file (input);
 
   if (config.map_file != NULL)
@@ -871,8 +930,7 @@ add_archive_element (struct bfd_link_info *info,
     }
 
   if (trace_files || trace_file_tries)
-    info_msg ("%I\n", input);
-
+    info_msg ("%I\n", &orig_input);
   return TRUE;
 }
 
@@ -889,6 +947,17 @@ multiple_definition (struct bfd_link_info *info ATTRIBUTE_UNUSED,
 		     asection *nsec,
 		     bfd_vma nval)
 {
+#ifdef ENABLE_PLUGINS
+  /* We may get called back even when --allow-multiple-definition is in
+     effect, as the plugin infrastructure needs to use this hook in
+     order to swap out IR-only symbols for real ones.  In that case,
+     it will let us know not to continue by returning TRUE even if this
+     is not an IR-only vs. non-IR symbol conflict.  */
+  if (plugin_multiple_definition (info, name, obfd, osec, oval, nbfd,
+	nsec, nval))
+    return TRUE;
+#endif /* ENABLE_PLUGINS */
+
   /* If either section has the output_section field set to
      bfd_abs_section_ptr, it means that the section is being
      discarded, and this is not really a multiple definition at all.
@@ -1371,7 +1440,10 @@ unattached_reloc (struct bfd_link_info *info ATTRIBUTE_UNUSED,
 
 /* This is called if link_info.notice_all is set, or when a symbol in
    link_info.notice_hash is found.  Symbols are put in notice_hash
-   using the -y option.  */
+   using the -y option, while notice_all is set if the --cref option
+   has been supplied, or if there are any NOCROSSREFS sections in the
+   linker script; and if plugins are active, since they need to monitor
+   all references from non-IR files.  */
 
 static bfd_boolean
 notice (struct bfd_link_info *info,
@@ -1387,9 +1459,17 @@ notice (struct bfd_link_info *info,
       return TRUE;
     }
 
-  if (! info->notice_all
-      || (info->notice_hash != NULL
-	  && bfd_hash_lookup (info->notice_hash, name, FALSE, FALSE) != NULL))
+#ifdef ENABLE_PLUGINS
+  /* We should hide symbols in the dummy IR BFDs from the nocrossrefs list
+     and let the real object files that are generated and added later trip
+     the error instead.  Similarly would be better to trace the real symbol
+     from the real file than the temporary dummy.  */
+  if (!plugin_notice (info, name, abfd, section, value))
+    return TRUE;
+#endif /* ENABLE_PLUGINS */
+
+  if (info->notice_hash != NULL
+	&& bfd_hash_lookup (info->notice_hash, name, FALSE, FALSE) != NULL)
     {
       if (bfd_is_und_section (section))
 	einfo ("%B: reference to %s\n", abfd, name);